<html window-frame="solid">
    <head>
        <title>Test</title>
        <style>

body {
    margin:0;
    background:gold;
}
        </style>
        <script|module>

  Window.this.on("spacechange", () => {

    if(!Window.this.isOnActiveSpace)
      Window.this.close();

  });

  document.body.append(<p>{Window.this.parameters}</p>);

        </script>
    </head>
    <body>
        Proxy window, should be closed on space change.
    </body>
</html>